In an electronic musical apparatus, a media ID (MD1, MD2, MD3, MD4, MD5) is associated with each recording media of a memory card 8, hard disk device 10, flash memory ROM 11, CD-ROM 12 and internet 15. Each media ID is encrypted to be recorded on a different position in a ROM 2. Upon reading a music...http://www.google.com.hk/patents/US7818258?utm_source=gb-gplus-share專利 US7818258 - Electronic musical apparatus for recording and reproducing music content
